Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations declare mutation with idempotentHint=true and destructiveHint=false, so safety is partly covered. The description still adds real behavioral value beyond them: it discloses merge semantics for unspecified settings, that no subscription is created, and that notification changes apply to existing webhook subscriptions without replaying old events.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three short sentences, front-loaded with the core action and merge semantics before the two boundary conditions. Each sentence carries distinct, non-redundant information (partial update, no subscription creation, no event replay).

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With an output schema present and annotations covering safety, the remaining burden is usage and side-effect clarity, which the description handles. The main residual gap is the credential/connection requirement for private calls, which the schema documents rather than the description.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

At 50% schema coverage, the nested `set` properties and `connection` carry their own descriptions, so the schema does most of the work. The description reinforces the semantics of `notifications` by explaining its effect on existing webhook subscriptions, but adds no format or requiredness detail beyond the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource (update settings for this agent) and immediately clarifies that it is a partial/merge update of only the supplied fields, which is non-obvious for a settings tool. It does not name tincan_settings_read as the read counterpart, so sibling differentiation relies on the agent noticing the name pairing.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The negative constraint 'Does not create monitoring subscriptions' usefully bounds when this tool is not the answer, and 'only the supplied settings' implies partial-update usage. However, no alternative tool is named and there is no explicit statement about when to prefer tincan_settings_read or a subscription-creating tool.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.